Soon after El Monte educator Bobby Salcedo was killed while visiting family in December, Rosemead High School teacher Mike Felix vowed never to travel south of the border until the murder was solved.

With Sunday’s grisly killing of three people connected to the U.S. Consulate in Ciudad Juarez, Mexico, Felix strengthened that promise.

“It’s just another sad case added onto here,” said Felix, who teaches in the same school district that Salcedo did. “It’s just more warning signs to our leaders.”

Suspected drug cartel members chased down and killed a consulate employee, her husband and the husband of a Mexican employee in separate incidents in Juarez, one of the world’s most dangerous cities. It borders El Paso, Texas.

It’s a tragic event some say will draw the ire of the U.S. government, which has already pledged its desire to solve the high-profile murder of Salcedo.

“Like the murder of (Salcedo) in Mexico last December, these latest deaths are further proof that Mexican drug violence knows no borders, and is increasingly affecting the United States and its citizens,” said Rep. Judy Chu, D-El Monte.

President Barack Obama also weighed in, with the White House saying Sunday he “shared in the outrage of the Mexican people” and pledged to work with Mexican authorities.

The FBI said Monday it would help Mexican authorities investigate the weekend murders, as it has for the past two months with Salcedo’s slaying.

With his statements, Obama finally showed he is paying attention to the violence in Mexico, said George W. Grayson, a professor at the College of William & Mary in Virginia, who has studied the drug cartels.

Salcedo, an El Monte City School District board member and assistant principal at El Monte High School, was killed in what his family believes was a case of being in the wrong place at the wrong time.

He and his wife, Betzy, were in a restaurant in Gomez Palacio, Durange with friends when gunmen grabbed him and five other men and later shot them on New Year’s Eve.

“We feel really sad for what happened to those families because we are going through the same thing,” Betzy Salcedo said in Spanish on Monday. “I hope they pay attention to their case as they did for my husband.”

No arrests have been made in connection with Salcedo’s death, said Chu, who has called for changes in U.S.-Mexico cooperation since his death.

The U.S. State Department on Monday urged American travelers to delay unnecessary travel to the northern states of Coahuila, Chihuahua and Durango, where Salcedo was killed.

As spring break for many U.S. universities approaches, the State Department also issued a new travel warning describing the dangers.

In response, some area schools sought to caution students headed to Mexico.

Azusa Pacific University planned to warn nearly 200 students headed on weeklong community service trips to Mexicali and Ensenada, university spokeswoman Allison Oster said.

At Whittier College, officials expected to send a mass e-mail to students Monday night telling them to avoid travel to Mexico, Dean of Students Jeanne Ortiz said.

Cal Poly Pomona, whose recess begins next week, has not issued a warning to students. But the administration hasn’t ruled it out, university spokeswoman Uyen Mai said.

Rep. Adam Schiff, D-Pasadena, said pledging law enforcement help to Mexican authorities is one way to solve this case. But for larger change, he said he was considering a legislative way to stem the flow of U.S. weapons to Mexico.

Los Angeles County is one of the leading U.S. sources of the weapons recovered at crime scenes in Mexico, many of which were drug-related, he said. Schiff said he met Monday with the head of the Bureau of Alcohol, Tobacco, Firearms and Explosives.

“It’s tragic that Mexico is increasingly looking like Columbia used to look,” Schiff said. “We have to do everything we can as a nation to scourge this violence.”

The renewed attention on violence in Mexico – and the resources likely to be devoted in response – could help bring an end to Salcedo’s case as well, said Rep. David Dreier, R-San Dimas.

“That’s exactly what we want to do,” he said. “We’re determined to bring justice.”

On Sunday, Juan Salcedo watched the news with his brother Carlos Salcedo, and heard similar pledges of bringing justice months before.

Juan Salcedo, who believes his brother’s case won’t be solved, said it’s another reminder it isn’t safe in Mexico.

“You can’t say it enough times, there is no reason to travel out there,” he said.

Staff Writer Tracy Garcia and The Associated Press contributed to this report.